Extraordinary discovery on Mars: Traces of ancient rivers...

Open University doctoral student Adam Losekoot and his team identified traces of ancient riverbeds in high-resolution images taken by NASA's Mars Reconnaissance Orbiter (MRO) and Mars Global Surveyor. The area studied covers an area of approximately 10 million square kilometers.

In a region of Mars called Noachis Terra, researchers have traced geological structures known as fluvial sinuous ridges: sedimentary layers from ancient riverbeds that hardened over time and rose to the surface as the surrounding softer ground eroded.

Some glacial rivers are a few hundred meters wide and 3-4 kilometers long, while larger structures can be about 1.6 km wider. MRO images have shown some rivers entering and filling craters, then continuing to flow over the crater walls.

The discovery suggests that Mars had a very different surface 3.7 billion years ago than its arid counterpart today. At that time, the planet's atmosphere was thicker, and liquid water could have existed on its surface. However, as Mars' magnetic field weakened over time, solar winds eroded the atmosphere, and much of the water escaped into space. These new findings suggest that the conditions necessary for life on Mars may have been more common in the past and contribute to our understanding of the evolution of water on the planet.